Some electronic devices are of sufficiently small size that a power supply cannot reasonably accompany the device. In these instances, the electronic device may receive power from an external power source. For example, in a typical Radio-frequency identification (RFID) implementation, an RFID chip receives power externally via an antenna to power the chip. Further, the same antenna may be used to both supply power and communication data to the RFID chip. Therefore, the external power source may be configured to supply power to the electronic device wirelessly.